Submission #631183

#	Time	Username	Problem	Language	Result	Execution time	Memory
631183		garam1732	Rarest Insects (IOI22_insects)	C++17	93.47 / 100	80 ms	664 KiB

insects

#include "insects.h"
#include <iostream>
#include <vector>
#include <stack>
#include <set>
#include <algorithm>
#include <cassert>
#define ff first
#define ss second
using namespace std;
typedef pair<int, int> pi;

//vector<int> ans;
//stack<pi> S, v;
vector<int> v, w;
set<int> s, u[2020];

int min_cardinality(int N) {
//    v.clear(); w.clear(); s.clear();
//    for(int i = 0; i < 2020; i++) u[i].clear();

    int num = 0;
    for(int i = 0; i < N; i++) {
        move_inside(i);
        num++;
        if(press_button() > 1) {
            move_outside(i);
            num--;
            s.insert(i);
        }
    }

    int sum = num;
    for(int i : s) {
        move_inside(i);
        u[press_button()].insert(i);
        sum++;
    }

    //cout<<num<<endl;
    int lb = 1, ub = N, mid;
    while(lb < ub) {
            mid = lb+ub+1>>1;

//            for(int i = lb+1; i <= ub+1; i++) {
//                cout<<i<<" : ";
//                for(int t:u[i])cout<<t<<" ";
//                cout<<endl;
//            }
//            cout<<endl;

            for(int i = ub+1; i > mid; i--) {
                for(int t : u[i]) {
                    move_outside(t);
                    sum--;
                }
            }

            //assert(press_button() == mid);
            for(int i = mid+1; i <= ub+1; i++) {
                for(int t : u[i]) {
                    move_inside(t);
                    if(press_button() > mid) {
                        move_outside(t);
                        w.push_back(t);
                    }
                    else {
                        sum++;
                        u[mid].insert(t);
                        v.push_back(t);
                    }
                }

                for(int t : v) u[i].erase(t);
                v.clear();
            }

            if(sum == mid*num) {
                for(int i = lb+1; i <= mid; i++)
                    for(int t : u[i])
                        s.erase(t);

                for(int i : s) {
                    move_inside(i);
                    sum++;
                }
                lb = mid;
            }
            else {
                for(int t : w) s.erase(t);
//                for(int t : u[mid]) move_outside(t);
//                sum -= u[mid].size();
                ub = mid-1;
            }
            w.clear();
    }

    return lb;
}

Compilation message (stderr)

insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:43:24: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   43 |             mid = lb+ub+1>>1;
      |                   ~~~~~^~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 68.47 / 75